Debt and Credit Facility - Summary of Interest Expense Relating to Senior Notes and Revolving Credit Facility (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Instrument [Line Items]
Total interest expense	$ 12.1	$ 12.2	$ 24.0	$ 24.4
Senior Notes and Revolving Credit Facility
Debt Instrument [Line Items]
Interest expense capitalized as construction in progress	(1.5)	(0.8)	(2.9)	(1.4)
Total interest expense	12.1	12.2	24.0	24.4
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving Credit Facility, including commitment fees and finance cost amortization	1.2	0.6	2.1	1.0
Senior Notes
Debt Instrument [Line Items]
Senior Notes. including debt issuance cost amortization	$ 12.4	$ 12.4	$ 24.8	$ 24.8

Debt related commitment fees and amortization of financing costs.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of interest capitalized during the period.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Aggregate amount of interest paid or due on all long-term debt.

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